Temperatures tonight to plunge below-freezing.

The mercury will rise into the upper 60s today but it will be dropping precipitously throughout the day as a polar vortex plunges south from the Arctic sending temperatures tumbling into negative values across the nation, according to meteorologists.

The National Weather Service in Melbourne predicts partly cloudy skies with a 20 percent chance of a passing shower. It will be windy with westerly gusts clocking up to 25 mph this afternoon.

The frigid air arrives tonight on a partly cloudy and breezy evening.

Forecasters expect the low to reach below freezing with wind chills in the teens after midnight.

A freeze warning is in effect from 1 a.m. to 9 a.m. tomorrow. Such temperatures can kill crops, plants and pets left outside if they are not protected. A lake wind advisory is also in effect.

It will be sunny Tuesday but don't be fooled.

The temperature will not top the upper 40s setting the stage for record-breaking reading and dangerously cold conditions for the region's most vulnerable.

The last time Orlando-area residents felt winter's chill so dramatically was in 2010 when low touched 29 degrees.